Today we tested for the first time the BLDC motors driven by the ODrive together with our VL53L0X ToF sensors. This simple demo program shows how the motors spin faster when something approaches the sensors.
Now that we have a small working setup we can build it all into an enclosure and start working on a program for the STM32F7. Hopefully we will soon have something that can drive around the house 🙂
As we mentioned before one of the most important parts of the robot are the wheels. The wheels are needed to transfer the motor power into pushing power. Without good wheels the wheels will slip and the motor power will be useless.For this reason we will make our own custom wheels with silicone rubber from VOSSCHEMIE.
It all starts by designing the wheel in 3D, for this we use FreeCAD.
To cast the wheel we need to have a mold for this we also use FreeCAD.
Next step is to 3D print everything.
Now we can finally start casting the wheels. For this we use 2 part silicone: SICOVOSS from our sponsor VOSSCHEMIE. Part A and B need to be mixed in a 1:1 ratio by weight. First we calculated the needed volume to fill the mold and calculated the desired mass we needed to fill the mold.
And then the mess could begin!
And here is the result after waiting a long time, the de-molding time would be between 6-7 hours but for this cast the time needed before be-molding took much longer. Probably because of the pigment used.
Final result !!
Thanks again VOSSCHEMIE for being our sponsor for the second time in a row!!!
For previous robots we relied on Arduino for the controlling unit. But this time we wanted to go to the next level and use a really advanced and capable microcontroller. Fast robots require fast brains, so we need a fast microcontroller. Last year I was a volunteer at The Things Conference from The Things Network. At the conference I was lucky enough to meet Benjamin Guilloud one of the Technical Marketing Engineers from STMicroelectronics.
STMicroelectronics is the only European microcontroller manufacturer and they have a big range of products, from microcontrollers to sensors.
I contacted Benjamin and asked if ST would like to support us by giving a development board and maybe a few of their Time Of Flight sensors. And yes they did, they send us a few development boards, a few Time Of Flight sensors and even some of their high-end microcontrollers. This sponsorship will not only give our robot the brains we need but also the eyes to find our opponents.
Thank you very much Benjamin and STMicroelectronics, your support is truly appreciated.
You may have a fast, smart and powerful robot. But none of this makes sense if your robot doesn’t have good grip on the arena. For this purpose many sumo robot builders cast custom rubber wheels or buy special wheels from the internet.
We wanted to make our own custom wheels and for this we teamed up with Vosschemie Benelux.
Vosschemie was already a sponsor for our previous robot, the wheels of the previous robot didn’t had any slip and they were even able to stall the motor. Because they offered so much grip we adhere to the silicone of Vosschemie Benelux.
The wheel making process for the wheels from the previous robot.
Today I went to Vosschemie Benelux in Lier to pick up the new sponsorship. We even got some green pigment to color the wheels.
Thank you very much Vosschemie Benelux for willing to be our sponsor again!!
The start of a successful CNC machined part is reliable work-piece holding. For this we made a threaded insert waste board so we don’t have to mess with double sided tape before we can machine something.
When the Shapeoko 3 arrived we still had to order a makita or dewalt router to use with it. We went with the makita but then not all the provided endmills fit into the machine so we had to make an adapter.
Afther doing some research on forums we found out about the ER11 collet which can be used as an universal “adapter”.
You can find all the necessary parts to do this at the instructable:
Shapeoko is by far our biggest sponsor. What they provided is unreal. They send us a Shapeoko 3 XL, this is a makers dream coming true. It is a “Desktop” CNC router which can cut wood, plastic and even some metals. This machine and sponsorship are incredible.
For our robot we’ll need to print a lot of prototypes to get things right the way we want for this we teamed up with Innofil3d and they and they send us 3 rolls of their ASA Natural filament. So now we’ll have enough filament to to prototype as much as we want and be able to print as much as possible of our 3d printed frame.
When you print exotic filaments the bed adhesion should be perfect otherwise you’ll risk that your prints start to warp. BuildTak is very popular for just this they provided us one of their BuildTak flexplate systems. So now we should be able to print these exotic filaments without any worries. Thank you BuildTak for saving our prints from warping!